GAP Crop Production & Protection 3 — Questions and Answers
Question 1: What does the term 'action threshold' mean in IPM for GAP-certified growers?
- The point at which crop yield drops below profit margin
- The pest population level at which intervention is economically justified (Correct answer)
- The maximum pesticide dose allowed per label
- The number of workers required to scout a field
Correct answer: The pest population level at which intervention is economically justified
An action threshold is the pest density at which control measures must be implemented to prevent economic loss.
Question 2: Which type of irrigation method is generally considered to reduce the risk of foliar contamination on fresh produce under GAP?
- Overhead sprinklers
- Furrow flood irrigation
- Drip or subsurface irrigation (Correct answer)
- Aerial misting systems
Correct answer: Drip or subsurface irrigation
Drip or subsurface irrigation delivers water directly to the root zone, avoiding direct contact with edible plant parts.
Question 3: Under GAP standards, when must pesticide applicators who apply federally restricted-use pesticides (RUPs) be certified?
- Only when applying to certified organic fields
- Always — before applying any RUP (Correct answer)
- Only when applying near schools or hospitals
- Only if the application exceeds 5 gallons
Correct answer: Always — before applying any RUP
Federal law requires that restricted-use pesticides be purchased and applied only by certified applicators or persons under their direct supervision.
Question 4: A GAP grower notices that a non-target weed species has developed resistance to a herbicide used repeatedly over five seasons. What is the best corrective action?
- Increase the herbicide application rate to overcome resistance
- Rotate to a herbicide with a different mode of action (Correct answer)
- Stop all herbicide use permanently
- Report the resistance to the EPA and await guidance
Correct answer: Rotate to a herbicide with a different mode of action
Rotating herbicides with different modes of action is the standard resistance management strategy to prevent and address herbicide-resistant weeds.
Question 5: What is the correct disposal method for empty pesticide containers under EPA and GAP requirements?
- Landfill disposal without rinsing
- Triple rinsing and then puncturing before disposal according to label instructions (Correct answer)
- Returning them to the manufacturer for reuse
- Burning them in the field to destroy residues
Correct answer: Triple rinsing and then puncturing before disposal according to label instructions
EPA regulations require triple rinsing (or pressure rinsing) of pesticide containers and following label instructions for proper disposal.
Question 6: Which biological control agent is commonly used under GAP to manage caterpillar pests on vegetable crops without synthetic insecticides?
- Glyphosate
- Bacillus thuringiensis (Bt) (Correct answer)
- Copper sulfate
- Mancozeb
Correct answer: Bacillus thuringiensis (Bt)
Bacillus thuringiensis (Bt) is a naturally occurring soil bacterium used as a biological insecticide effective against lepidopteran larvae.
Question 7: Why is it important to calibrate spray equipment regularly under GAP pesticide application standards?
- To reduce the number of field workers needed
- To ensure accurate application rates, preventing under- or over-application (Correct answer)
- To increase equipment lifespan and reduce maintenance costs
- To comply with EPA registration renewal requirements
Correct answer: To ensure accurate application rates, preventing under- or over-application
Regular calibration ensures pesticides are applied at label-specified rates, protecting crop safety, efficacy, and compliance.
GAP Crop Production & Protection 3
What does the term 'action threshold' mean in IPM for GAP-certified growers?